Framebuilders - 1 inch conduit bender to bend frok stays??

Anybody has used this relatively non expensive conduit benders to bend fork stays?? Some are big enough so the curve radius gets pretty long/big... anybody? experiences???

Just asking because is faster just get one of those than cut and fabricate a bender at home with wood and stuff.

Thanks.

I've thought about this myself. I think the difficulty would be in repeatability of bends, i.e. getting two blades bent exactly the same.

I used one many years ago, in fact that's what drove me to make my own bender.

The stop on most conduit benders is about 2 inches from the edge of the radial segment the tube gets bent over, that leaves a 2 inch straight section at the bottom of the blade.
To start the bend closer to the end of the blade you'll need to add a stop closer to the segment, not too tough to do.

I think you'll end up flattening the blades. Making one out of wood or even steel is not that big of a deal.

Interesting, well the device has marks the thing is to find one big enough because i think the curve in the 1 inch one is too small. Maybe u guys are right, might be better just to make one, Hmm... have some piece of laminated floor moving around...

I think i found the perfect piece of wood and is even already cut... I bought long time ago this corner of an ikea desk, I took it off and put it in the garage, today while cleaning the garage i found it and it could work great i believe. What I was thinking is to cut an old tubular rim and put it to the sides around the edge to just keep the blades center. Can't remember what I paid but wasn't that expensive.

Anybody likes the idea?


http://i1085.photobucket.com/albums/j426/ultraman6970/Forkbendermaybe.jpg

it might be a little too narrow, and the radius isn't right. I think that would be perfect for bending top tubes

Hmm... do you have plans with a cut out of the radius that should be?

Anybody has used this relatively non expensive conduit benders to bend fork stays?? Yup.

Been using one made by Ideal #74-031 (labeled 1/2" EMT) for 12 years now. I clamp the bender handle in the bench vice (not the fork), measure and mark each blade and alternate bending - a little on one blade, then repeat on the other. Successfully tweaked about 30 road forks so far and have yet to wrinkle or kink one. However, I would strongly discourage bending MTB forks with this method.

are you just tweaking, or starting from new blades?

Here's Tim Paterek's fork blade bender from an early version of the Paterek Manual, which can be downloaded free from http://www.timpaterek.com/paterek.pdf.

http://i32.photobucket.com/albums/d7/k4drd/Bicycles/Sanner%20Framebuilding%20Class/TimPaterekForkBladeBender.jpg

are you just tweaking, or starting from new blades?

New ones, my master builder retired and i got stuck with tubes and lugs so why not give it a try. My other option to avod the issue bending the blades is getting a 7 degree fork crown and just go straight.

Thanks!


Here's Tim Paterek's fork blade bender from an early version of the Paterek Manual, which can be downloaded free from http://www.timpaterek.com/paterek.pdf.

http://i32.photobucket.com/albums/d7/k4drd/Bicycles/Sanner%20Framebuilding%20Class/TimPaterekForkBladeBender.jpg

HI, measured the radius in the table piece i had and is 43.83cm that is around 17.5 inches... is that a problem?

consider making 2 duplicate curved forms, stack cutting on a bandsaw, perhaps?

then build the fork with straight blades, bend the completed fork .
that should result in consistent symmetrical rakes.

HI, measured the radius in the table piece i had and is 43.83cm that is around 17.5 inches... is that a problem?

Depends on the curve you want. 17.5" would make a big ugly curve, imo. Classic rando forks are usually around 6-7". My personal form has an increasing radius that starts at 6.5" and ends at 8.5"...it's all in your sense of aesthetics.

consider making 2 duplicate curved forms, stack cutting on a bandsaw, perhaps?

then build the fork with straight blades, bend the completed fork .

that should result in consistent symmetrical rakes.

But then you end up with a straight section right at the dropouts. Bending the blades before any brazing gives you a much greater control over the appearance of the finished fork.

Ok, you guys were right, it is too much radius. I made a cardboard fork using my radius and looks aweful, have another idea tho, hope this one works.

But then you end up with a straight section right at the dropouts. Bending the blades before any brazing gives you a much greater control over the appearance of the finished fork.

This is not always true. Masi Carlsbad and Mario Confente both brazed them up straight then raked them. if you look at the bend it appears parabolic, and the fixture was too.

This is not always true. Masi Carlsbad and Mario Confente both brazed them up straight then raked them. if you look at the bend it appears parabolic, and the fixture was too.

Just googled a bunch of Confente and Old Masi pics, and while I don't know where you see a parabola, all the pics illusrate my point. All of the blades had a small straight section right behind the drop which is what happens when you bend the blades with the drop brazed in. Not a big deal either way, but like I said before, cutting the blades after bending gives you more control over the final appearance.